private void mouseUp(object sender, MouseEventArgs e)
{
this.MouseMove -= this.mouseMove;
if (!dragging)
for (int i = buttons.Count - 1; i >= 0; i--)
if (pointInPolygon(e.Location, buttons[i].ClickLocation))
{
buttons[i].onClicked(e);
break;
}
dragging = false;
}